Patent Literature 1 mentions that, in an input apparatus, when temperature control by a temperature regulator is not satisfactorily performed, to change a control degree by control parameters, a correction degree value is calculated and output to the temperature regulator. Specifically, a correlative degree distribution is displayed on a CRT concerning a plurality of parameters. When a user performs pressing operation on the CRT, the position of the pressing is displayed on the CRT, a vector starting from the origin and ending at the pressing position is decomposed into vector components to calculate a correction degree value, and the correction degree value is output to the temperature regulator. Consequently, according to Patent Literature 1, by intuitively performing a correlative degree input concerning a plurality of parameters through visual inspection, it is possible to easily obtain degree values having a proper correlation as degree values of the respective parameters.
Patent Literature 2 mentions that, in a control-model adjusting apparatus, a graph of an input response characteristic of a transfer function representing a dynamic characteristic model of a control target is displayed on a screen and, when slider bars of a gain, a time constant, and a dead time are moved up and down by a pointer, the graph on the screen is simultaneously changed according to the movement of the slider bars. Consequently, according to Patent Literature 2, by adjusting the graph representing the dynamic characteristic model of the control target on the screen, it is possible to perform work of modeling of the dynamic characteristic model, which conventionally requires a great deal of labor, in a short time without requiring special expertise.
Patent Literature 3 mentions that, in a PID tuning apparatus, a curved line representing a step response characteristic of an automatic control system and broken lines representing control parameters (a rise time, an overshoot amount, and a control stabilization time) are displayed on a screen and, when an operator moves the broken lines representing the control parameters, PID tuning is performed and the curved line on the screen changes according to the movement of the broken lines. Consequently, according to Patent Literature 3, it is possible to perform the PID tuning according to control parameters corresponding to an actual movement of a control target process.